We've found 3 phrases for unreliable (0.131 seconds):

a stopped clock is right twice a day »    A normally unreliable person or instrument can occasionally provide correct information, even if only by accident.

bolt bucket »    A machine, especially an automobile. Implies that the machine is clunky or unreliable.

garbage in, garbage out »    (computing, information technology) If input data is not complete, accurate, and timely, then the resulting output is unreliable and of no useful value.1963, Raymond Crowley, "Robot Tax Collector Seeks Indications of 'Fudging'," Times Daily (Alabama, USA), 1 April (retrieved 26 July 2010):Officials explained that the quality of the computer's work depends on the quality of the data fed into it. Neil Hoke, administrative assistant to Stewart, quoted an adage of computer men: "Garbage in, garbage out."2008, Roger K. Lewis, "'In Architectural Design, Brains and Talent Trump the Best Software," Washington Post, 19 July (retrieved 26 July 2010):The old caveat "GIGO"

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